The present invention relates to a device and method for repairing pipe using hydrophilic seals.
Prior methods for repairing damaged pipe lines include moving a liner tube impregnated with a liquid material capable of curing and hardening to the position within the pipe where the damaged portion occurs. The liner tube is urged in an outward radial direction into contact with the pipe line being repaired and the liquid material impregnating the liner tube is permitted to cure and harden. As a result the liner tube forms an interior liner for the pipe being repaired.
On some occasions lateral pipe lines are connected to main pipe lines. Often damage occurs at the junction between the lateral pipe line and the main pipe line. T-shaped or y-shaped liner tubes have been utilized to fit within the junction between the lateral pipe line and the main line. Liner tubes, after hardening form a T-shaped or y-shaped liner to the interior of the junction between the lateral pipe line and the main pipe line.
Ground water outside the lateral pipe line and the main pipe line infiltrates through the damaged portion of the pipe line and between the liner tube and the pipe line to the point where it can enter the pipe line. In order to prevent this infiltration of ground water, attempts have been made to adhere the liner tube to the interior surface of the tube being repaired, whether it is a single straight pipe line or a T-shaped or y-shaped pipe line.
However, considerable difficulty has been encountered in attempting to obtain an adhesive bond between the liner tube and the interior of the pipe being repaired. The interior of the pipe being repaired is often greasy or oily and covered with debris. Attempts have been made to wash the interior of the pipe line with some success, but the washing of the interior of the pipe line is often only partial and is not reliable. Furthermore, in some types of pipes such as polyethylene pipes, an adhesive bond cannot be obtained between the resin impregnated liner tube and the polyethylene pipe.
T-shaped or y-shaped liner tubes hinder this infiltration of ground water, but are also sometimes unreliable. When these T-shaped or y-shaped liner tubes are utilized, there is the possibility of water infiltration between the liner tube and the pipes being repaired.
Therefore, a primary object of the present invention is the provision of an improved device and method for repairing pipe using hydrophilic seals.
A further object of the present invention is the provision of a device and method for repairing pipe wherein the hydrophilic seals provide a water tight seal between the pipe liner and the pipe being repaired.
A further object of the present invention is the provision of a device and method for repairing pipe using hydrophilic bands which surround the liner tube and which are positioned between the liner tube and the pipe being repaired.
A further object of the present invention is the provision of a device and method for repairing pipe using hydrophilic seals between the liner tube and the pipe being repaired, the hydrophilic seals expanding in response to encountering ground water or liquid to provide a water tight seal between the liner tube and the pipe being repaired.
A further object of the present invention is the provision of a device and method for repairing pipe using hydrophilic seals which prevent entry of ground water or other liquid from outside the pipe being repaired to the inside of the pipe being repaired.
A further object of the present invention is the provision of a device and method for repairing pipe which uses hydrophilic seals that expired in the presence of water to provide a seal against entry of ground water for a lateral pipe by itself, a main pipe by itself or a combination of a lateral pipe joined with a main pipe.
A further object of the present invention is the provision of a device and method for repairing pipe which includes circular and stretchable rubber band-like hydrophilic seals that surround the liner and hold the liner around a launcher as the launcher and liner are moved within the pipe line.
A further object of the present invention is the provision of a device and method for repairing pipe which includes stretchable and circular rubber band-like hydrophilic seals that can expand in an outward radial direction in response to outward radial expansion of the liner tube against the pipe being repaired.
A further object of the present invention is the provision of a device and method for repairing pipe which holds the liner tube firmly in place around a launcher or carrier as the unit is robotically positioned within the pipe line.
A further object of the present invention is the provision of a device and method for repairing pipe using hydrophilic seals which is economical to manufacture, durable in use, and reliable in operation.